The Stabilizing Effect of Intraspecific Genetic Variation on Population Dynamics in Novel and Ancestral Habitats
The Stabilizing Effect of Intraspecific Genetic Variation on Population Dynamics in Novel and Ancestral Habitats
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DOI：
10.1086/600085
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发表时间：
2009-08-01
影响因子：
2.9
通讯作者：
Agashe, Deepa
中科院分区：
文献类型：
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作者：
Agashe, Deepa
最近的研究表明，无性繁殖物种的种内遗传变异可能对群落和生态系统功能产生巨大影响，增加其稳定性，生产力和物种丰富度。然而，关于其种群影响的主要问题仍然没有得到经验上的回答：（a）种内遗传多样性如何影响有性物种的生态特征，其中重组可以改变选择和生态位多样化等因果机制的结果？(b)遗传多样性增加种群动态稳定性吗？(c)遗传多样性的影响取决于选择环境吗？为了回答这些问题，我建立了复制面粉甲虫（赤拟谷盗）种群，这些种群具有不同程度的生态相关性，可遗传的性状变异，并监测了大约八代的动态。我表明，人口的稳定性和持久性增加更大的遗传变异，但稳定的影响是独立的选择性栖息地（不同比例的祖先和新的资源）。等位基因从一个单一的创始菌株进行了选择性的扫描在同质的祖先栖息地，但不是在一个新的异质栖息地。这些结果扩大了目前的理解，遗传多样性的生态影响表明，遗传上更多样化的性种群持续时间更长，更稳定，但选择性的环境决定的机械基础增加稳定性。
Recent studies show that intraspecific genetic variation in asexual species may have large effects on community and ecosystem functions, increasing their stability, productivity, and species richness. However, major questions regarding its population-level impact remain empirically unanswered: (a) How does intraspecific genetic diversity affect the ecological characteristics of sexual species, in which recombination can alter the outcome of causal mechanisms such as selection and niche diversification? (b) Does genetic diversity increase population dynamic stability? (c) Is the impact of genetic diversity dependent on the selective environment? To answer these questions, I founded replicate flour beetle (Tribolium castaneum) populations with different degrees of ecologically relevant, heritable trait variation and monitored their dynamics for approximately eight generations. I show that population stability and persistence increased with greater genetic variation but that the stabilizing effect was independent of the selective habitat (different proportions of ancestral and novel resources). Alleles from a single founding strain underwent a selective sweep in the homogeneous ancestral habitat but not in a novel heterogeneous habitat. These results expand current understanding of the ecological impacts of genetic diversity by showing that genetically more diverse sexual populations persist longer and are more stable but that the selective environment determines the mechanistic basis of increased stability.